JP7486719B2 - Hybrid vehicle control device - Google Patents

Description

The present invention relates to a control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmitting and cutting off torque between the engine and the motor.

Conventionally, in a hybrid vehicle equipped with an engine and a motor as a power source and driven by at least one of the driving force of the engine and the driving force of the motor, a technology has been proposed for cranking the engine with the motor to start the engine. For example, Patent Document 1 discloses a technology for suppressing torque shock occurring in the vehicle due to clutch engagement by changing the motor torque based on the transmission torque of a clutch provided between the engine and the motor when transitioning from a mode in which the vehicle runs on motor torque to a mode in which the vehicle runs on engine and motor torque.

JP 2018-30507 A

Conventionally, motors (typically permanent magnet motors) have been widely used that have the characteristic that the torque they generate gradually decreases as the rotation speed increases. When a motor with such characteristics is applied to a hybrid vehicle, a relatively large deceleration may occur in the hybrid vehicle when starting the engine when switching from a driving mode in which the hybrid vehicle runs using the motor torque without using the engine torque (hereinafter referred to as the "first driving mode" as appropriate) to a driving mode in which the hybrid vehicle runs using at least the engine torque (hereinafter referred to as the "second driving mode" as appropriate). The reason for this is as follows.

When a motor having the above-mentioned characteristics is used, when the motor speed is relatively high in the first driving mode, the torque that the motor can generate is relatively small. If the torque that the motor can generate is relatively small in the first driving mode, when switching from the first driving mode to the second driving mode, the motor may not be able to generate enough torque to start the engine when using the torque of the motor to start the engine (i.e., when cranking the engine using the motor). In this case, the kinetic energy of the hybrid vehicle while it is running is used to start the engine, that is, torque is drawn from the vehicle side to the engine. As a result, when switching from the first driving mode to the second driving mode, a relatively large deceleration occurs due to the decrease in the kinetic energy of the hybrid vehicle, which may cause the driver to feel uncomfortable.

The present invention has been made to solve the problems of the conventional technology described above, and aims to provide a control device for a hybrid vehicle having an engine, a motor, and a clutch provided between them, which can appropriately suppress the discomfort felt by the driver due to the occurrence of deceleration when switching from a driving mode using the motor to a driving mode using the engine.

In order to achieve the above object, the present invention provides a control device for a hybrid vehicle having an engine, a motor, and a clutch for switching between transmission and interruption of torque between the engine and the motor, the control device including: a driving mode determination means for determining whether or not to switch the driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using torque of the motor without using torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least torque of the engine; and a motor for performing control to reduce an output torque of the motor by a predetermined amount when it is determined by the driving mode determination means that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode. the motor control means for controlling the engine is provided with a motor control means, a clutch control means for transitioning the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means, and a cranking control means for cranking the engine by the motor to start the engine during and/or after control by the clutch control means , and when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode, if the driver of the hybrid vehicle has performed an operation related to the movement of the hybrid vehicle, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if no operation is performed, the motor control means performs control to reduce the output torque of the motor by a predetermined amount .

In the present invention configured in this manner, when switching from the first driving mode to the second driving mode, the control device for the hybrid vehicle performs control to reduce the motor output torque by a predetermined amount, and then transitions the clutch from a released state to an engaged state and cranks the engine using the motor to start the engine. In other words, when switching from the first driving mode to the second driving mode, the control device for the hybrid vehicle performs control to reduce the motor output torque by a predetermined amount before starting the engine, thereby reducing the forward acceleration of the hybrid vehicle by a predetermined amount in advance.

According to the present invention, even if the motor is unable to generate sufficient torque required to start the engine when starting the engine to switch driving modes, it is possible to reduce the change in acceleration when the acceleration of the hybrid vehicle in the traveling direction decreases to a deceleration that corresponds to the shortfall in the motor's output torque. This makes it possible to prevent the driver from feeling uncomfortable as if the hybrid vehicle is suddenly being dragged backwards when the engine is started in response to switching from the first driving mode to the second driving mode.

Furthermore , even when switching from the first driving mode to the second driving mode, if there is an operation by the driver regarding the movement of the hybrid vehicle, control to reduce the motor output torque by a predetermined amount is not performed, so that the engine can be started quickly and the driver's request regarding the movement of the hybrid vehicle can be appropriately realized.

In the present invention, the hybrid vehicle preferably further comprises an automatic transmission provided on a power transmission path between the engine/motor and the drive wheels and including a planetary gear.
In an automatic transmission equipped with planetary gears, the inertia is large, so a decrease in forward acceleration is likely to occur when switching driving modes. However, by applying the control according to the present invention as described above to a hybrid vehicle equipped with such an automatic transmission, it is possible to reduce the change in acceleration when the forward acceleration decreases, thereby preventing the driver from feeling uncomfortable as if the hybrid vehicle is suddenly being dragged backwards.

A control device for a hybrid vehicle according to another aspect of the present invention is a control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmission and cut-off of torque between the engine and the motor, and includes a driving mode determination means that determines whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using torque of the motor without using torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least torque of the engine, and when it is determined by the driving mode determination means that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode, a control is performed to reduce an output torque of the motor by a predetermined amount. the engine control system includes a motor control means for switching the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means; and a cranking control means for cranking the engine by the motor to start the engine during and/or after control by the clutch control means, wherein when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from a first driving mode to a second driving mode, if the amount of change in accelerator opening of the hybrid vehicle is equal to or greater than a predetermined amount, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if the amount of change in accelerator opening is not equal to or greater than the predetermined amount, performs control to reduce the output torque of the motor by a predetermined amount .
A control device for a hybrid vehicle according to another aspect of the present invention is a control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmission and interruption of torque between the engine and the motor, the control device including: a driving mode determination means that determines whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using torque of the motor without using torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least torque of the engine; and a control device that reduces an output torque of the motor by a predetermined amount when it is determined by the driving mode determination means that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode. the motor control means for controlling the motor output torque by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from a first driving mode to a second driving mode and operation of the brake pedal of the hybrid vehicle is detected, and the motor control means for controlling the motor output torque by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from a first driving mode to a second driving mode and operation of the brake pedal is detected, the motor control means does not perform control to reduce the motor output torque by a predetermined amount when operation of the brake pedal is not detected .
A control device for a hybrid vehicle according to another aspect of the present invention is a control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmission and interruption of torque between the engine and the motor, the control device including: a driving mode determination means that determines whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using torque of the motor without using torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least torque of the engine; and a control circuit that reduces an output torque of the motor by a predetermined amount when it is determined by the driving mode determination means that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode. the motor control means performs control to switch the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means; and cranking control means performs cranking of the engine by the motor to start the engine during and/or after control by the clutch control means, wherein when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from a first driving mode to a second driving mode, if a gear shift instruction operation is detected in the hybrid vehicle, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if a gear shift instruction operation is not detected, performs control to reduce the output torque of the motor by a predetermined amount .
A control device for a hybrid vehicle according to another aspect of the present invention is a control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmission and cut-off of torque between the engine and the motor, and includes a driving mode determination means that determines whether or not to switch the driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using torque of the motor without using torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least the torque of the engine, and a control that reduces an output torque of the motor by a predetermined amount when it is determined by the driving mode determination means that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode. the motor control means performs control to reduce the output torque of the motor by a predetermined amount when the sports mode switch of the hybrid vehicle is operated when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from a first driving mode to a second driving mode, and when the sports mode switch is not operated when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from a first driving mode to a second driving mode, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount .
A control device for a hybrid vehicle according to another aspect of the present invention is a control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmission and interruption of torque between the engine and the motor, the control device including: a driving mode determination means that determines whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using torque of the motor without using torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least torque of the engine; and a control device that reduces an output torque of the motor by a predetermined amount when it is determined by the driving mode determination means that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode. the motor control means for controlling the engine output of the hybrid vehicle by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from a first driving mode to a second driving mode, and the motor control means for controlling the engine output of the hybrid vehicle by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from a first driving mode to a second driving mode, and for controlling the engine output of the hybrid vehicle by a predetermined amount when the sports mode of the hybrid vehicle is turned on .

The hybrid vehicle control device of the present invention can appropriately suppress the discomfort felt by the driver due to the occurrence of deceleration when switching from a driving mode using a motor to a driving mode using an engine.

1 is a schematic configuration diagram of a hybrid vehicle to which a control device for a hybrid vehicle according to an embodiment of the present invention is applied; 1 is a block diagram showing an electrical configuration of a control device for a hybrid vehicle according to an embodiment of the present invention; 4 is a flowchart showing a driving mode switching control for a hybrid vehicle according to an embodiment of the present invention. 4 is a flowchart showing engine start control according to an embodiment of the present invention. 4 shows an example of a time chart when control of a hybrid vehicle according to an embodiment of the present invention is executed. 1 shows an example of a time chart when control of a hybrid vehicle is executed according to a conventional technique.

The following describes a hybrid vehicle control device according to an embodiment of the present invention with reference to the attached drawings.

<Device Configuration>
FIG. 1 is a schematic diagram of a hybrid vehicle to which a control device for a hybrid vehicle according to an embodiment of the present invention is applied.

As shown in FIG. 1, the hybrid vehicle 1 mainly includes an engine 2 (e.g., a gasoline engine) that generates torque for driving the hybrid vehicle 1, a motor 4 that is provided downstream of the engine 2 on the power transmission path of the hybrid vehicle 1 and generates torque for driving the hybrid vehicle 1, a battery 5 that exchanges power with the motor 4 via an inverter (not shown), a transmission 6 that is provided downstream of the motor 4 on the power transmission path of the hybrid vehicle 1 and changes the rotation speed of the engine 2 and/or the motor 4, a power transmission system 8 that transmits torque from the transmission 6 downstream, a drive shaft 10 that drives the drive wheels 12 with torque from the power transmission system 8, and the drive wheels 12.

The output shaft of the engine 2 and the rotating shaft of the motor 4 are coaxially connected by the axis AX1 via the first clutch CL1, which can be connected or disconnected. This first clutch CL1 allows the transmission and disconnection of torque between the engine 2 and the motor 4 to be switched on and off. For example, the first clutch CL1 is configured as a dry multi-plate clutch that can change the transmission torque capacity by continuously or stepwise controlling the clutch hydraulic oil flow rate and the clutch hydraulic pressure by a motor (not shown).

The rotating shaft of the motor 4 and the rotating shaft of the transmission 6 are coaxially connected by the axis AX2. The transmission 6 is an automatic transmission that typically includes one or more planetary gear sets including a sun gear S1, a ring gear R1, a pinion gear P1 (planetary gear), and a carrier C1, and frictional fastening elements such as clutches and brakes, and has the function of automatically switching gear stages (gear ratios) according to vehicle speed, engine speed, etc. The ring gear R1 is arranged concentrically with the sun gear S1, and the pinion gear P1 is arranged between the sun gear S1 and the ring gear R1 so as to mesh with the sun gear S1 and the ring gear R1. The carrier C1 holds the pinion gear P1 so that it can rotate on its own axis and revolve around the sun gear S1. The transmission 6 also includes a second clutch CL2 that can be connected and disconnected, and the second clutch CL2 can switch between transmitting and disconnecting torque between the upstream side of the transmission 6 (the engine 2 and the motor 4) and the downstream side of the transmission 6 (the driving wheels 12, etc.). For example, the second clutch CL2 is also configured with a dry multi-plate clutch that can change the transmission torque capacity by continuously or stepwise controlling the clutch hydraulic oil flow rate and the clutch hydraulic pressure by a motor (not shown). The second clutch CL2 is actually configured with a number of clutches used to switch between various gear stages in the transmission 6. For simplicity, only one planetary gear set is shown in FIG. 1, but in reality the transmission 6 includes a number of planetary gear sets. By selectively engaging frictional fastening elements such as a number of clutches represented by the second clutch CL2 and a number of brakes (not shown) to switch the power transmission path through each planetary gear set, it is possible to realize, for example, a number of forward gear stages and one reverse gear stage.

Torque is input to the power transmission system 8 via the output shaft AX3 of the transmission 6. The power transmission system 8 includes a differential gear that distributes the driving force to a pair of left and right drive wheels 12, a final gear, and the like.

The hybrid vehicle 1 described above can switch between driving modes by switching between engagement and release of the first clutch CL1. That is, the hybrid vehicle 1 has a first driving mode in which the first clutch CL1 is set to a released state and the hybrid vehicle 1 is driven using the torque of the motor 4 without using the torque of the engine 2, and a second driving mode in which the first clutch CL1 is set to an engaged state and the hybrid vehicle 1 is driven using at least the torque of the engine 2. The first driving mode is a so-called EV driving mode, and the second driving mode includes an engine driving mode in which the hybrid vehicle 1 is driven using only the torque of the engine 2, and a hybrid driving mode in which the hybrid vehicle 1 is driven using the torque of both the engine 2 and the motor 4.

The motor 4 used in this embodiment has the characteristic that the higher the rotation speed, the smaller the torque generated. In other words, the motor 4 has the characteristic that the lower the rotation speed, the greater the torque generated. In particular, the torque of the motor 4 is approximately maximum when the rotation speed is less than a predetermined value, and when the rotation speed is equal to or greater than the predetermined value, the torque decreases as the rotation speed increases. For example, a permanent magnet motor is used as such a motor 4.

Next, FIG. 2 is a block diagram showing the electrical configuration of a control device for a hybrid vehicle according to an embodiment of the present invention.

As shown in FIG. 2, the controller 20 receives a signal from an engine speed sensor SN1 that detects the speed of the engine 2, a signal from a motor speed sensor SN2 that detects the speed of the motor 4, a signal from an accelerator opening sensor SN3 that detects the accelerator opening corresponding to the amount of depression of the accelerator pedal by the driver, a signal from a vehicle speed sensor SN4 that detects the vehicle speed of the hybrid vehicle 1, a signal from an acceleration sensor SN5 that detects the longitudinal acceleration of the hybrid vehicle 1, and a signal from an SOC sensor SN6 that detects the SOC (State of Charge) that indicates the state of charge of the battery 5.

The controller 20 is configured by a computer having one or more processors 20a (typically a CPU), various programs interpreted and executed on the processor (including basic control programs such as an OS, and application programs that are started on the OS and realize specific functions), and memory 20b such as a ROM or RAM for storing programs and various data. The controller 20 functions as the "driving mode determination means", "motor control means", "clutch control means", and "cranking control means" of the "control device for a hybrid vehicle" in this invention.

Specifically, the controller 20 mainly outputs control signals to the engine 2, the motor 4, the first clutch CL1, and the second clutch CL2 based on the detection signals from the above-mentioned sensors SN1 to SN6, and controls them. For example, the controller 20 performs control to adjust the ignition timing, fuel injection timing, and fuel injection amount of the engine 2, control to adjust the rotation speed and torque of the motor 4, and control to switch between engagement and release of the first and second clutches CL1 and CL2. Note that in practice, the controller 20 controls the ignition plugs, fuel injection valves, throttle valves, etc. of the engine 2, controls the motor 4 via an inverter, and controls the first and second clutches CL1 and CL2 via a hydraulic control circuit.

<Hybrid vehicle control>
Next, the contents of the control performed by the controller 20 in the embodiment of the present invention will be described. In the present embodiment, the controller 20 performs control for starting the engine 2 (engine start control) when switching from a first driving mode (EV driving mode) in which the hybrid vehicle 1 is driven using the torque of the motor 4 to a second driving mode (engine driving mode or hybrid driving mode) in which the hybrid vehicle 1 is driven using at least the torque of the engine 2. In this case, the controller 20 performs the engine start control by controlling the engine 2, the motor 4, the first clutch CL1, and the second clutch CL2.

First, an overview of the engine start control according to this embodiment will be described. As described above, when switching from the first driving mode to the second driving mode, a relatively large deceleration may occur in the hybrid vehicle 1. This is because, when switching from the first driving mode to the second driving mode, the torque of the motor 4 is used to start the engine 2 (i.e., the engine 2 is started by cranking using the motor 4), but the motor 4 may not be able to generate enough torque (including the resistance of the engine 2, the variation of the first clutch CL1, and the loss in the transmission 6; the same applies below) required to start the engine 2. In this case, the kinetic energy of the traveling hybrid vehicle 1 is used to start the engine 2. As a result, in the hybrid vehicle 1, the acceleration in the traveling direction is reduced to a deceleration equivalent to the shortage of the output torque of the motor 4 relative to the torque required to start the engine 2. If the change in acceleration at this time is large, the driver may feel a sense of discomfort as if the hybrid vehicle 1 is suddenly dragged backwards.

In order to address the above-mentioned problems, in this embodiment, when switching from the first driving mode to the second driving mode, the controller 20 performs control to reduce the output torque of the motor 4 by a predetermined amount, and then transitions the first clutch CL1 from a released state to an engaged state, and cranks the engine 2 using the motor 4 to start the engine 2. In other words, in this embodiment, when switching from the first driving mode to the second driving mode, the controller 20 reduces the output torque of the motor 4 by a predetermined amount before starting the engine 2.

This allows the travel direction acceleration of the hybrid vehicle 1 to be reduced in advance by a predetermined amount by reducing the output torque of the motor 4 before starting the engine 2 to switch the driving mode. As a result, even if the motor 4 cannot generate sufficient torque required to start the engine 2, it is possible to reduce the change in acceleration when the travel direction acceleration decreases to a deceleration corresponding to the shortage of the output torque of the motor 4. This makes it possible to prevent the driver from feeling a strange sensation as if the hybrid vehicle 1 is suddenly being dragged backwards when the engine 2 is started in response to switching from the first driving mode to the second driving mode.

On the other hand, in this embodiment, even when switching from the first driving mode to the second driving mode, if there is a driver operation related to the movement of the hybrid vehicle 1 (typically, if the change in accelerator opening corresponding to the driver's operation of the accelerator pedal is equal to or greater than a predetermined amount), the controller 20 does not perform control to reduce the output torque of the motor 4 by a predetermined amount as described above. In this case, the controller 20 transitions the first clutch CL1 from the released state to the engaged state without reducing the output torque of the motor 4, and cranks the engine 2 by the motor 4 to start the engine 2. This is done in order to start the engine 2 quickly, in order to prioritize responsiveness to the driver's operation over suppressing the acceleration change as described above.

In this embodiment, even when switching from the first driving mode to the second driving mode, if the change in acceleration when the acceleration in the travel direction decreases to the deceleration corresponding to the shortage of the output torque of the motor 4 is equal to or less than a predetermined value (for example, a change in acceleration that does not cause the driver to feel uncomfortable), the controller 20 does not perform control to reduce the output torque of the motor 4. That is, even in this case, the controller 20 transitions the first clutch CL1 from the released state to the engaged state without reducing the output torque of the motor 4, and cranks the engine 2 by the motor 4 to start the engine 2. For example, when the motor rotation speed is low and the motor 4 is in a state where it can generate almost maximum torque, and when the motor 4 alone can output the torque required for cranking the engine 2 with the auxiliary equipment such as the air conditioner in a non-operating state, the controller 20 cranks the engine 2 by the motor 4 to start the engine 2 without reducing the output torque of the motor 4. In this case, the output torque of the motor 4 is not insufficient, so the decrease in the acceleration in the travel direction does not occur, and the driver does not feel uncomfortable.

In this embodiment, the controller 20 first controls the second clutch CL2 to transition from an engaged state to a slip state when there is a request to switch from the first driving mode to the second driving mode, both in cases where the output torque of the motor 4 is reduced in advance and in cases where it is not. The reason why the second clutch CL2 is put into a slip state in this way is that when starting the engine 2, the kinetic energy of the hybrid vehicle 1 that is running is transferred to the engine 2 side and used to start the engine 2, and a decrease in the acceleration in the traveling direction is suppressed as much as possible.

By setting the second clutch CL2 to a completely released state, it is possible to reliably prevent the kinetic energy of the hybrid vehicle 1 from being transmitted to the engine 2. However, once the second clutch CL2 is set to a completely released state in this way, it takes time to switch the second clutch CL2 to an engaged state, making it difficult to switch the driving mode quickly. Therefore, in this embodiment, when there is a request to switch from the first driving mode to the second driving mode, the second clutch CL2 is set to a slip state. The second clutch CL2 is fully engaged after the engine 2 is ignited.

However, even if the second clutch CL2 is set to a slip state, the inertia of the second clutch CL2 causes a decrease in the forward acceleration of the hybrid vehicle 1. Specifically, when a certain amount of torque is transmitted by the second clutch CL2 that is in a slip state rather than a completely released state, the kinetic energy of the hybrid vehicle 1 is also used to increase the revolution speed of the planetary gears in the transmission 6, and the forward acceleration decreases.

In contrast, in this embodiment, when switching from the first driving mode to the second driving mode, the controller 20 reduces the output torque of the motor 4 by a predetermined amount before starting the engine 2, thereby reducing the forward acceleration of the hybrid vehicle 1 by a predetermined amount. As a result, even if the motor 4 cannot generate sufficient torque required to start the engine 2 and increase the revolution speed of the planetary gears in the transmission 6, it is possible to reduce the change in acceleration when the forward acceleration decreases to a deceleration equivalent to the shortage of the output torque of the motor 4. This makes it possible to prevent the driver from feeling a strange sensation as if the hybrid vehicle 1 is suddenly being dragged backwards when switching from the first driving mode to the second driving mode.

Next, the driving mode switching control according to an embodiment of the present invention will be specifically described with reference to Figures 3 and 4. Figure 3 is a flowchart showing the driving mode switching control of the hybrid vehicle 1 according to an embodiment of the present invention. This driving mode switching control is a process for switching the driving mode from the first driving mode to the second driving mode, and is repeatedly executed by the controller 20 at a predetermined cycle. Figure 4 is a flowchart showing the engine start control according to an embodiment of the present invention, which is executed in the driving mode switching control.

First, when the driving mode switching control shown in FIG. 3 is started, in step S11, the controller 20 acquires various information about the hybrid vehicle 1, including information corresponding to the detection signals from the above-mentioned sensors SN1 to SN6. Then, the controller 20 proceeds to step S12.

In step S12, the controller 20 determines whether the current driving mode is the first driving mode (EV driving mode). For example, the controller 20 makes this determination based on the control signals output to the motor 4, the first clutch CL1, and the second clutch CL2. In this example, the controller 20 determines that the current driving mode is the first driving mode when the first clutch CL1 is released, the second clutch CL2 is engaged, and torque is output from the motor 4. When the controller 20 determines that the current driving mode is the first driving mode (step S12: Yes), the controller 20 proceeds to step S13. On the other hand, when the controller 20 determines that the current driving mode is not the first driving mode (step S12: No), typically when the current driving mode is the second driving mode, the controller 20 ends the driving mode switching control. In this case, since the engine 2 is in an operating state, it is not necessary to execute the engine start control to start the engine 2.

In step S13, the controller 20 determines whether there is a request to switch from the first driving mode to the second driving mode, in other words, whether there is a request to start the engine 2. In one example, the controller 20 determines that there is a request to switch to the second driving mode when the SOC of the battery 5 detected by the SOC sensor SN6 is less than a predetermined value (for example, a lower limit value of the SOC at which the battery 5 should be charged, which is determined from the viewpoint of protecting the battery 5, or an SOC at which the battery 5 is prohibited from taking out electric power, etc.). In another example, the controller 20 determines that there is a request to switch to the second driving mode when the air conditioner switch of the hybrid vehicle 1 is turned on by the driver. In yet another example, the controller 20 determines that there is a request to switch to the second driving mode when there is a relatively large acceleration request from the driver (for example, when the driver depresses the accelerator pedal heavily). When the controller 20 determines that there is a request to switch from the first driving mode to the second driving mode (step S13: Yes), the controller 20 proceeds to step S14. On the other hand, if the controller 20 determines that there is no request to switch from the first driving mode to the second driving mode (step S13: No), the controller 20 ends the driving mode switching control. In this case, the first driving mode is maintained, so there is no need to execute the engine start control to start the engine 2.

In step S14, the controller 20 determines whether or not there is an operation related to the movement of the hybrid vehicle 1 by the driver. In one example, the controller 20 determines that there is an operation related to the movement of the hybrid vehicle 1 when the change amount of the accelerator opening detected by the accelerator opening sensor SN3 is equal to or greater than a predetermined amount. In another example, the controller 20 determines that there is an operation related to the movement of the hybrid vehicle 1 when the brake pedal operation is detected by the brake pedal sensor (not shown), when a gear shift instruction operation is detected by the shift lever or paddle shift, when the steering wheel is operated, when the sports mode switch is operated, etc. In yet another example, when the sports mode is turned on by the sports mode switch, it is assumed that high responsiveness is always required by the driver, and it is determined that there is an operation related to the movement of the hybrid vehicle 1. If the controller 20 determines that there is an operation related to the movement of the hybrid vehicle 1 by the driver (step S14: No), it proceeds to step S17 and executes engine start control. In this case, the controller 20 executes engine start control without reducing the output torque of the motor 4 in advance to start the engine 2 quickly and prioritize the request from the driver. On the other hand, if the controller 20 determines that the driver has not performed any operation related to the movement of the hybrid vehicle 1 (step S14: Yes), the controller 20 proceeds to step S15.

In step S15, the controller 20 determines whether the estimated decrease in the acceleration in the traveling direction of the hybrid vehicle 1 (estimated acceleration decrease) when engine start control is executed is greater than the maximum allowable value of the decrease in the acceleration in the traveling direction (allowable acceleration decrease).

The allowable acceleration reduction amount is the maximum amount of reduction in the acceleration in the traveling direction that is allowed during engine start control. Specifically, the allowable acceleration reduction amount is determined in advance based on the range of acceleration reduction amounts that do not cause discomfort to the driver and the range of acceleration reduction amounts required for the reliability of the hybrid vehicle 1. In this embodiment, for example, the allowable acceleration reduction amount is 0.02 G. In addition, the estimated acceleration reduction amount can be calculated as the difference between the current acceleration and the estimated deceleration that is estimated to occur in the hybrid vehicle 1 when the engine start control is executed. The estimated deceleration can be calculated by multiplying the torque balance obtained by subtracting the torque required to start the engine 2 and the torque required to cancel the running resistance from the torque that the motor 4 can output, by a predetermined coefficient. This predetermined coefficient is determined based on the current gear stage of the transmission 6, the tire diameter, the weight of the hybrid vehicle 1, and the like. In this embodiment, for convenience, a torque balance of 10 Nm corresponds to an acceleration of 0.01 G of the hybrid vehicle 1. That is, for example, when the torque balance is -15 Nm, the estimated deceleration is -0.015 G. In addition, the controller 20 can determine the torque that the motor 4 can output based on the rotation speed of the motor 4 detected by the motor rotation speed sensor SN2 by referring to a map (prestored in the memory 20b of the controller 20) that shows the relationship between the rotation speed of the motor 4 and the torque that can be output. In addition, in this embodiment, for the sake of convenience, the torque required to start the engine 2 is set to 90 Nm, and the torque required to cancel the running resistance is set to 10 Nm, but these values can be set appropriately depending on the configuration of the engine 2 of the hybrid vehicle 1, the vehicle speed, etc.

If the controller 20 determines that the estimated acceleration reduction amount is equal to or less than the allowable acceleration reduction amount (step S15: No), the process proceeds to step S17 and executes engine start control. In this case, since it is considered that the driver will not feel uncomfortable even if engine start control is executed immediately, the controller 20 executes engine start control without reducing the output torque of the motor 4 in advance. On the other hand, if the controller 20 determines that the estimated acceleration reduction amount is greater than the allowable acceleration reduction amount (step S15: Yes), the process proceeds to step S16.

In step S16, the controller 20 reduces the output torque of the motor 4 so that the estimated acceleration reduction amount is equal to or less than the allowable acceleration reduction amount. Specifically, the controller 20 reduces the output torque of the motor 4 so as to reduce the acceleration in the traveling direction of the hybrid vehicle 1 by an amount equivalent to the difference between the estimated acceleration reduction amount and the allowable acceleration reduction amount. For example, if the estimated acceleration reduction amount is 0.03 G and the allowable acceleration reduction amount is 0.02 G, the difference (i.e., the excess of the estimated acceleration reduction amount) is 0.01 G. In this case, the torque equivalent to this difference of 0.01 G is 10 Nm, so the controller 20 reduces the output torque of the motor 4 by 10 Nm. The controller 20 then proceeds to step S17.

In step S17, the controller 20 executes engine start control. After the engine 2 is started by the engine start control, the controller 20 ends the driving mode switching control.

Next, engine start control according to an embodiment of the present invention will be described with reference to FIG. 4. This engine start control is executed in step S17 in FIG. 3.

When engine start control is started, in step S21, the controller 20 sets the torque (hereinafter referred to as the "second clutch target slip torque") to be applied to the second clutch CL2 when the second clutch CL2 is put into a slip state during engine start. Specifically, the controller 20 determines the second clutch target slip torque based on the gear currently set in the transmission 6 and the current torque of the motor 4. Here, the minimum torque (hereinafter referred to as the "second clutch minimum torque") that can be applied to the second clutch CL2 in a slip state is determined according to the gear. Therefore, in a typical example, the controller 20 determines the second clutch minimum torque corresponding to the current gear based on the relationship between the gear and the second clutch minimum torque (such as a map specified in advance), and sets this second clutch minimum torque as the second clutch target slip torque.

The reason why the second clutch minimum torque depends on the gear of the transmission 6 is because, as described above, the second clutch CL2 corresponds to a number of clutches for switching between various gears in the transmission 6. In other words, the clutches that make up the second clutch CL2 change depending on the gear, and this causes the minimum slip torque by the second clutch CL2 to change as well.

Next, in step S22, the controller 20 controls the second clutch CL2 so as to gradually transition the second clutch CL2 to a slip state. Specifically, the controller 20 transitions the second clutch CL2, which is in an engaged state, toward the release side until the torque of the second clutch CL2 reaches the second clutch target slip torque set in step S21. Then, the controller 20 maintains the state (slip state) of the second clutch CL2 to which the second clutch target slip torque is applied.

Next, in step S23, the controller 20 controls the first clutch CL1 so as to gradually transition the first clutch CL1 to a slip state. That is, the controller 20 transitions the first clutch CL1 from the released state toward the engaged side. For example, the controller 20 transitions the first clutch CL1 to a predetermined slip state just before full engagement. In addition, the controller 20 transitions the first clutch CL1 to a slip state in this manner, and transmits the torque of the motor 4 to the engine 2 side via the first clutch CL1, thereby cranking the engine 2 with the torque of the motor 4 to increase the engine speed. In this case, the controller 20 performs control to gradually increase the torque of the motor 4 while maintaining the speed of the motor 4 almost constant. Typically, the controller 20 increases the torque of the motor 4 to the maximum torque that can be output at the current speed. After this, the torque transmitted to the engine 2 (i.e. the torque applied to the first clutch CL1) reaches the torque required to start the engine 2, but the controller 20 keeps the first clutch CL1 in a predetermined slip state until the timing to ignite the engine 2 arrives.

Next, in step S24, the controller 20 controls the engine 2 to ignite the engine 2 when the timing for igniting the engine 2 is reached. That is, the controller 20 executes ignition by the spark plug to combust the mixture in the engine 2. Then, in step S25, the controller 20 controls the first clutch CL1 in a slipping state to fully engage the first clutch CL1. Specifically, the controller 20 fully engages the first clutch CL1 at a timing when the engine speed and the motor speed are almost the same. Then, in step S26, the controller 20 controls the second clutch CL2 in a slipping state to fully engage the second clutch CL2. Specifically, the controller 20 fully engages the second clutch CL2 at a timing when the engine speed (equals the motor speed) and the speed obtained by converting the vehicle speed into a gear ratio match. Then, the controller 20 ends the engine start control.

<Action and effect>
Next, the operation and effects of the control device for a hybrid vehicle according to the embodiment of the present invention will be described.

Figure 5 shows an example of a time chart when control of the hybrid vehicle 1 according to an embodiment of the present invention is executed. Figure 6 shows an example of a time chart when switching of the driving mode is executed by the conventional technology. In Figures 5 and 6, the upper time chart shows the change over time in the acceleration (including deceleration) of the hybrid vehicle 1, and the lower time chart shows the torque of the motor 4, the engine 2, etc. (specifically, the torque at the output shaft of the motor 4).

In order to explain the operation and configuration of the driving mode switching control according to this embodiment, the results of the driving mode switching control according to this embodiment are shown in Fig. 5, and the results of switching the driving mode according to the conventional technology are shown as a comparative example in Fig. 6. The graphs in Fig. 5 and Fig. 6 show the time changes of the following parameters.
Graph G10: Acceleration of the hybrid vehicle 1 Graph G11: Output torque of the motor 4 Graph G12: Torque (negative value) required to counteract the running resistance
Graph G13: Torque required to start engine 2 (negative value)
Graph G14: Output torque of engine 2 after starting Graph G15: Torque balance (total value of G11 to G14)
Graph G20: Acceleration of the hybrid vehicle 1 Graph G21: Output torque of the motor 4 Graph G22: Torque (negative value) required to counteract the running resistance
Graph G23: Torque required to start engine 2 (negative value)
Graph G24: Output torque of engine 2 after starting Graph G25: Torque balance (total value of G21 to G24)

In the example of the conventional technology shown in Figure 6, from before time t1 when the hybrid vehicle 1 is running in the first driving mode until after time t5 when the hybrid vehicle 1 is running in the second driving mode, the torque required to cancel out the driving resistance is constant at -10 Nm (see graph G22). Also, before time t1, the output torque of the motor 4 is 25 Nm (see graph G21). Therefore, the torque balance is 15 Nm (see graph G25), and the acceleration of the hybrid vehicle 1 corresponding to this torque balance is 0.015 G (see graph G20).

In the example of the conventional technology in FIG. 6, when it is determined at time t1 that there is a request to switch from the first driving mode to the second driving mode, engine start control is immediately started. Then, between time t1 and time t3, the magnitude of the torque required to start the engine 2 increases to 90 Nm (see graph G23. The torque required to start the engine 2 is shown as a negative value, so it decreases on the graph). Between time t1 and time t2, the output torque of the motor 4 also increases in accordance with the increase in the torque required to start the engine 2 (see graph G21), so the torque balance is kept constant at 15 Nm (see graph G25). That is, there is no change in the acceleration of the hybrid vehicle 1. However, after the output torque of the motor 4 reaches a maximum value of 85 Nm at time t2, the output torque of the motor 4 does not increase. Therefore, between time t2 and time t3, the torque balance decreases in accordance with the increase in the torque required to start the engine 2 (see graph G25). Then, when the magnitude of the torque required to start the engine 2 reaches a maximum value of 90 Nm at time t3, the torque balance is 85-10-90=-15 Nm (see graph G25). The acceleration of the hybrid vehicle 1 corresponding to this torque balance is -0.015 G (see graph G20). Therefore, the amount of acceleration reduction from the acceleration of 0.015 G at time t1 when the engine start control was initiated is 0.03 G. In other words, in the conventional technology illustrated in FIG. 6, the amount of reduction in the traveling direction acceleration of the hybrid vehicle 1 during engine start control exceeds the allowable acceleration reduction amount of 0.02 G that does not cause the driver to feel uncomfortable, and therefore there is a possibility that the driver will feel uncomfortable.

On the other hand, even in this embodiment illustrated in FIG. 5, the torque required to cancel out the running resistance is constant at -10 Nm from before time t1 when the hybrid vehicle 1 is running in the first running mode until after time t6 when the hybrid vehicle 1 is running in the second running mode (see graph G12). Also, before time t1, the output torque of the motor 4 is 25 Nm (see graph G11). Therefore, the torque balance before time t1 is 15 Nm (see graph G15), and the acceleration of the hybrid vehicle 1 corresponding to this torque balance is 0.015 G (see graph G10).

In the example of this embodiment in FIG. 5, as in the example of the conventional technology shown in FIG. 6, it is determined that there is a request to switch from the first driving mode to the second driving mode at time t1. However, if the engine start control is started immediately at time t1 as in the example of the conventional technology, the amount of decrease in the acceleration in the traveling direction of the hybrid vehicle 1 during the engine start control reaches 0.03 G, which may cause the driver to feel uncomfortable. Therefore, in the example of this embodiment in FIG. 5, the controller 20 reduces the output torque of the motor 4 by a predetermined amount between times t1 and t2 before executing the engine start control. In the example of FIG. 5, the estimated acceleration decrease amount is 0.03 G and the allowable acceleration decrease amount is 0.02 G, so the difference (i.e., the excess of the estimated acceleration decrease amount) is 0.01 G. That is, the torque corresponding to this difference of 0.01 G is 10 Nm, so the controller 20 reduces the output torque of the motor 4 by 10 Nm between times t1 and t2 to 15 Nm (see G11). As a result, the torque balance at time t2 is 15-10=5 Nm, and the acceleration of the hybrid vehicle 1 corresponding to this torque balance is 0.005 G (see graph G10).

After that, between time t2 and time t4, the magnitude of the torque required to start the engine 2 increases to 90 Nm (see graph G13. The torque required to start the engine 2 is shown as a negative value, so it decreases on the graph). Between time t2 and time t3, the output torque of the motor 4 also increases in accordance with the increase in the torque required to start the engine 2 (see graph G11), so the torque balance is kept constant at 5 Nm (see graph G15). That is, there is no change in the acceleration of the hybrid vehicle 1. However, after the output torque of the motor 4 reaches the maximum value of 85 Nm at time t3, the output torque of the motor 4 does not increase. Therefore, between time t3 and time t4, the torque balance decreases in accordance with the increase in the torque required to start the engine 2 (see graph G15). Then, when the magnitude of the torque required to start the engine 2 reaches the maximum value of 90 Nm at time t4, the torque balance becomes 85-10-90=-15 Nm (see graph G15). The acceleration of the hybrid vehicle 1 corresponding to this torque balance is -0.015 G (see graph G10). Therefore, the amount of acceleration reduction from the acceleration of 0.005 G at time t2 when engine start control is initiated is 0.02 G. That is, in the example of this embodiment shown in FIG. 5, the amount of reduction in the traveling direction acceleration of the hybrid vehicle 1 during engine start control is equal to or less than 0.02 G, which is the allowable acceleration reduction amount that does not cause the driver to feel uncomfortable, so that the discomfort felt by the driver can be suppressed.

After time t4, the engine 2 is ignited at time t5, and then the first clutch CL1 and the second clutch CL2 are fully engaged until time t6, at which time the driving mode of the hybrid vehicle 1 is switched to the second driving mode.

As described above, in this embodiment, when switching from the first driving mode to the second driving mode, the controller 20 performs control to reduce the output torque of the motor 4 by a predetermined amount, and then transitions the first clutch CL1 from a released state to an engaged state, and cranks the engine 2 using the motor 4 to start the engine 2. In other words, in this embodiment, when switching from the first driving mode to the second driving mode, the controller 20 performs control to reduce the output torque of the motor 4 by a predetermined amount before starting the engine 2, thereby reducing the forward acceleration of the hybrid vehicle 1 by a predetermined amount in advance.

As a result, even if the motor 4 is unable to generate sufficient torque required to start the engine 2 when starting the engine 2 to switch the driving mode, it is possible to reduce the change in acceleration when the acceleration in the traveling direction of the hybrid vehicle 1 decreases to a deceleration that corresponds to the shortfall in the output torque of the motor 4. This makes it possible to prevent the driver from feeling a strange sensation as if the hybrid vehicle 1 is suddenly being dragged backwards when the engine 2 is started in response to switching from the first driving mode to the second driving mode.

In addition, according to this embodiment, even when switching from the first driving mode to the second driving mode, if there is an operation by the driver regarding the movement of the hybrid vehicle 1, the controller 20 does not perform control to reduce the output torque of the motor 4 by a predetermined amount. This allows the engine 2 to be started quickly, and the driver's request regarding the movement of the hybrid vehicle 1 to be appropriately realized.

This embodiment is also applied to a hybrid vehicle 1 equipped with a transmission 6 (automatic transmission) equipped with planetary gears. In a transmission 6 (automatic transmission) equipped with planetary gears, the inertia is large, so that the decrease in the acceleration in the traveling direction when switching the driving mode as described above is likely to occur. However, according to this embodiment, before starting the engine 2, control is performed to reduce the output torque of the motor 4 by a predetermined amount, and the acceleration in the traveling direction of the hybrid vehicle 1 is reduced by a predetermined amount in advance. Even if the motor 4 cannot sufficiently generate the torque required to start the engine 2 and increase the revolution speed of the planetary gear in the transmission 6, the acceleration change when the acceleration in the traveling direction decreases to a deceleration corresponding to the shortage of the output torque of the motor 4 can be reduced. This makes it possible to suppress the driver from feeling a strange sensation as if the hybrid vehicle 1 was suddenly dragged backward when switching from the first driving mode to the second driving mode.

REFERENCE SIGNS LIST 1 Hybrid vehicle 2 Engine 4 Motor 6 Transmission 12 Drive wheels 20 Controller 20a Processor 20b Memory CL1 First clutch CL2 Second clutch P1 Pinion gear

Claims (7)

A control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmitting and interrupting torque between the engine and the motor,
a driving mode determination means for determining whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using the torque of the motor without using the torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least the torque of the engine;
a motor control means for performing control to reduce an output torque of the motor by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode;
a clutch control means for transitioning the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means;
a cranking control means for cranking the engine by the motor in order to start the engine during and/or after control by the clutch control means;
having
When the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode, if a driver of the hybrid vehicle performs an operation related to the movement of the hybrid vehicle, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if the driver of the hybrid vehicle does not perform the operation, the motor control means performs control to reduce the output torque of the motor by a predetermined amount.
A control device for a hybrid vehicle. A control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmitting and interrupting torque between the engine and the motor,
a driving mode determination means for determining whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using the torque of the motor without using the torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least the torque of the engine;
a motor control means for performing control to reduce an output torque of the motor by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode;
a clutch control means for transitioning the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means;
a cranking control means for cranking the engine by the motor in order to start the engine during and/or after control by the clutch control means;
having
When the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode, if a change in an accelerator opening of the hybrid vehicle is equal to or greater than a predetermined amount , the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if a change in the accelerator opening is not equal to or greater than the predetermined amount , the motor control means performs control to reduce the output torque of the motor by a predetermined amount .
A control device for a hybrid vehicle. A control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmitting and interrupting torque between the engine and the motor,
a driving mode determination means for determining whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using the torque of the motor without using the torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least the torque of the engine;
a motor control means for performing control to reduce an output torque of the motor by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode;
a clutch control means for transitioning the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means;
a cranking control means for cranking the engine by the motor in order to start the engine during and/or after control by the clutch control means;
having
When the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode, if an operation of a brake pedal of the hybrid vehicle is detected, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if an operation of the brake pedal is not detected, the motor control means performs control to reduce the output torque of the motor by a predetermined amount.
A control device for a hybrid vehicle. A control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmitting and interrupting torque between the engine and the motor,
a driving mode determination means for determining whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using the torque of the motor without using the torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least the torque of the engine;
a motor control means for performing control to reduce an output torque of the motor by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode;
a clutch control means for transitioning the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means;
a cranking control means for cranking the engine by the motor in order to start the engine during and/or after control by the clutch control means;
having
When the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode, if a gear shift command operation is detected in the hybrid vehicle, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if the gear shift command operation is not detected, the motor control means performs control to reduce the output torque of the motor by a predetermined amount.
A control device for a hybrid vehicle. A control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmitting and interrupting torque between the engine and the motor,
a driving mode determination means for determining whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using the torque of the motor without using the torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least the torque of the engine;
a motor control means for performing control to reduce an output torque of the motor by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode;
a clutch control means for transitioning the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means;
a cranking control means for cranking the engine by the motor in order to start the engine during and/or after control by the clutch control means;
having
When the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode, if a sports mode switch of the hybrid vehicle is operated, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if the sports mode switch is not operated, performs control to reduce the output torque of the motor by a predetermined amount.
A control device for a hybrid vehicle. A control device for a hybrid vehicle having an engine, a motor, and a clutch that switches between transmitting and interrupting torque between the engine and the motor,
a driving mode determination means for determining whether or not to switch a driving mode of the hybrid vehicle from a first driving mode in which the clutch is set to a released state and the hybrid vehicle is driven using the torque of the motor without using the torque of the engine, to a second driving mode in which the clutch is set to an engaged state and the hybrid vehicle is driven using at least the torque of the engine;
a motor control means for performing control to reduce an output torque of the motor by a predetermined amount when the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode;
a clutch control means for transitioning the clutch from a released state to an engaged state so that the torque of the motor is transmitted to the engine via the clutch after control by the motor control means;
a cranking control means for cranking the engine by the motor in order to start the engine during and/or after control by the clutch control means;
having
When the driving mode determination means determines that the driving mode of the hybrid vehicle is to be switched from the first driving mode to the second driving mode, if a sports mode is on in the hybrid vehicle, the motor control means does not perform control to reduce the output torque of the motor by a predetermined amount, and if the sports mode is not on, performs control to reduce the output torque of the motor by a predetermined amount.
A control device for a hybrid vehicle. 7. The control device for a hybrid vehicle according to claim 1 , further comprising an automatic transmission provided on a power transmission path between the engine and the motor and drive wheels, the automatic transmission including a planetary gear.

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